The present invention relates generally to methods of recording onto CD-R media, and more particularly to an improved recording method which is suitable for use with CD-R media having recorded on their outermost track only a blank segment, representing, for example, a gap between music pieces, and which allows a track body portion (namely, track-specific recording data), such as a main body of a music piece, to be additionally written onto the track.
CD-R drives for recording onto CD-R media are generally constructed in such a manner that each time data recording is terminated on a track of the disk, information (including position information) of the just-recorded track (hereinafter referred to as xe2x80x9ctrack-descriptive informationxe2x80x9d for convenience of description) is recorded in the PMA (Program Memory Area) area of the CD-R medium located inwardly of the disk""s lead-in area. When recording is resumed on the disk, information indicative of the recording end point of the recorded track is read out from the PMA area so that recording data can be written onto another track following the recording end point of the preceding recorded track. But, in case data recording onto a given track is halted compulsorily due to a power shutdown, or in case writing to the PMA area fails due to some reason although data recording onto a given track has been made appropriately, there would arise a situation where no track-descriptive information for the track is recorded in the PMA area. If the CD-R drive carries on with data writing onto a next track following the recording end point of the preceding track, on the basis of the information read out from the PMA area, without noticing presence of such a track (hereinafter also called a xe2x80x9cdamaged trackxe2x80x9d), the data would be written over an already-recorded portion of the preceding track, which thereby unavoidably leads to a recording failure. To avoid such inconveniences, it has been conventional to determine, for each newly loaded or inserted CD-R medium, whether there is any track for which track-descriptive information is not recorded in the PMA area of the medium and, if there is such a track, perform a process for recording the missing track-descriptive information, including the recording end point information, of that track into the PMA area so that accurate data writing is permitted onto a next track following the recording end point of the preceding track.
Further, some audio CD recorders, which directly receive audio signals reproduced from audio source equipment and record the thus-received audio signals onto a CD-R or CD-RW medium in the CD format, are constructed to previously record only blank segments, each representing a gap between music pieces (i.e., silent inter-music-piece signals), so that the main body of each designated music piece can be recorded simultaneously with a user""s recording start operation while saving waiting time that would otherwise be required for recording the inter-music-piece signal before the main body of each music piece. If the CD-R medium, having recorded thereon only the inter-music-piece signals via the CD-R recorder, is loaded into the CD-R drive having the above-mentioned function of completing or finalizing a damaged track, the CD-R drive would consider all the tracks to be damaged tracks since no track-descriptive information is recorded in the PMA area although the inter-music-piece signals do constitute part of the corresponding tracks, and thus automatically perform the track finalizing process by recording the track-descriptive information in the PMA area of the CD-R medium. As a consequence, there would be produced xe2x80x9cdefective tracksxe2x80x9d having no recordings of the main body portions of music pieces at all. Further, because such defective tracks each have a zero effective length, they can not comply with the requirement of the CD standard that each track should have a 4 sec. length or more.
In view of the foregoing, it is an object of the present invention to provide a recording method which is suitable for use with a CD-R medium having recorded on its outermost track only a blank segment representing, for example, a gap between music pieces and which allows a track body portion, such as a main body of a music piece, to be additionally written onto the track.
In order to accomplish the above-mentioned object, the present invention provides an improved CD-R medium recording method which comprises: a step of detecting an outermost track for which track-descriptive information is not yet recorded in a PMA area of a CD-R medium and track-specific recording data are already recorded in a program area by a track-at-once scheme; a step of determining whether recording on the outermost track is terminated at the end of a first-type area, such as a blank segment (inter-music-piece gap) in the case of music recording, where a Q subcode INDEX is at a value of 0 or is made up to a second-type area, such as a program area, where the Q subcode INDEX is at a value of 1 or greater; a step of, if the recording on the outermost track is terminated at the end of the first-type area, additionally writing the track-specific recording onto the outermost track starting at the beginning of the second-type area following the first-type area and then recording the track-descriptive information for the outermost track into the PMA area; and a step of, if the recording on the outermost track is made up to the second-type area, recording the track-descriptive information for the outermost track into the PMA area without additionally writing the track-specific recording data onto the outermost track.
According to another aspect of the present invention, there is provided a CD-R medium recording method which comprises: a step of accessing a lead-in area and PMA area of a CD-R medium to read out information recorded in the lead-in area and PMA area; a step of accessing a location on the CD-R medium immediately following a recording end point represented by the information read out from the lead-in area and PMA area; a step of determining whether or not there is a track recorded by a track-at-once scheme at the accessed location; a step of, if there is the track recorded by the track-at-once scheme at the accessed location, searching for a recording end point of an outermost track and determining whether recording on the outermost track is terminated at the end of a first-type area where a Q subcode INDEX is at a value of 0 or is made up to a second-type area where the Q subcode INDEX is at a value of 1 or greater; a step of, if the recording on the outermost track is terminated at the end of the first-type, additionally writing track-specific recording data onto the outermost track starting at the beginning of the second-type area following the first-type area and then recording track-descriptive information for the outermost track into the PMA area; and a step of, if the recording on the outermost track is made up to the second-type area, recording the track-descriptive information for the outermost track into the PMA area without additionally writing the track-specific recording data onto the outermost track.
Whether or not the recording on the outermost track is terminated at the end of the first-type area, represented by the Q subcode INDEX value 0, may be determined by ascertaining that the recording is terminated at a relative time position of 00:00:00 or 00:00:01 in the first-type area. Further, after completion of the recording into the PMA area, recording onto a next track may be made following the recording end point of the outermost track.
According to the CD format, the INDEX of the Q subcode is recorded as a value xe2x80x9c0xe2x80x9d in each inter-music-piece gap (blank segment), but, in a main body (track body) segment of each music piece, it is recorded as a value incrementing from xe2x80x9c1xe2x80x9d up to xe2x80x9c99xe2x80x9d as necessary. When an outmost track is detected for which track-descriptive information is not yet recorded in a PMA area, it can be known whether the outermost track is one having only an inter-music-piece gap (blank segment) recorded thereon or is a real damaged track that has both the inter-music-piece gap and main body segment of a music piece recorded thereon, by determining whether the recording on the outmost track is terminated at the end of the first-type area represented by the Q subcode INDEX value 0 or is made up to the second-type area represented by the Q subcode INDEX value 1 or greater. If the the outermost track is the one having only an inter-music-piece gap (blank segment) recorded thereon, the main body or track-specific recording data of a music piece is additionally written onto the track before the track is finalized, so that it is possible to avoid formation of a defective track with no music piece main body (track-specific recording data) which does not comply with the CD standard.